All posts tagged "Astronomy"

09/29/2012

The planets are sticking close to the horizon
during prime viewing hours for most of October, making them more of a challenge
to see. After sunset on October evenings, look to the left of where the sun was
to catch Mars (and maybe even Saturn) low on the horizon. Saturn is sinking and
joining the sun, where it reaches conjunction toward the end of the month, but
the Red Planet will stay just above the horizon for the rest of the year. On
October 1, Mars will be in Libra, heading toward the claws of Scorpius.

The moon can guide you to some of the planets in
mid-October. Try spotting Mercury on October 16 and 17. Mercury shines at
magnitude -0.1, making it brighter than Mars, but its location closer to the
sun leaves it in the sunset’s bright glow as the evening begins. On October 16,
Mercury is just to the upper left of the slender crescent moon. On October 17,
the moon is between Mercury (to the moon's lower right) and Mars (to the moon's
upper left). On October 18, the crescent moon will lie to the upper left of
magnitude 1.2 Mars, with the Red Planet’s reddish rival Antares (the Anti-Ares)
shining a bit brighter at magnitude 1.0 just below Mars.

08/28/2012

In early August, Mars, Saturn and Spica formed a triangle.
Credit: John
Chumack

The Harvest Moon, which is defined as the Full Moon closest
to the autumnal equinox, can occur in September or October. Most years the
Harvest Moon is in September, as it is in 2012. The equinox, and therefore the
first day of fall, lands on September 22 at 7:49
a.m. Pacific Time. With days and nights of equal
length, the sun rises directly in the east and sets directly in the west. The
closest Full Moon to this date is on September 29. The Harvest Moon rises in
the east just before it hits 100 percent illumination at 8:19
p.m. pacific.

Moonrise in September occurs as little as a half hour apart
from night to night as opposed to other times of the year when moonrise from
one night to the next can fall more than an hour apart. The full and nearly
full moons after sunset in September provided the extra light for farmers in
the fields and earned this moon the name of Harvest Moon.

The planet Uranus reaches opposition, or opposite the sun in
the sky when it rises at sunset and sets at sunrise, on the same night as the
Full Moon, September 29. Normally opposition is considered the best time to
observe a planet, but when it occurs simultaneously with a Full Moon in the
same region of sky, this is not the case. The moon will be just four degrees
above Uranus, washing out the sky around the dim planet.

07/27/2012

The saying "once in a blue moon" is meant to represent something of rare occurrence. A blue moon is commonly thought of as the second full moon in one calendar month, and August's first full moon occurs on August 1 at 8:27 p.m. Pacific Time, meaning that 29.5 days later another full moon will occur in August, on the 31st at 6:58 a.m. PDT. The next blue moon will not occur until July 2015.

Blue moons aren't named for their color. The moon will look like any other full moon on August 31. But on occasion the moon can take on different hues due to particles in our atmosphere acting as a filter. Smoke from forest fires and ash from volcanoes have been known to produce darker moons, sometimes with a blue or purplish tinge.

The planets put on a good show in August regardless of whether you are a morning person or a night owl. In the early morning hours before sunrise, the brilliant Venus and Jupiter can be spotted in the east. Watch on August 11 through 14 when the crescent moon moves toward and then through the planetary pairing.

In the evening, Mars has been closing in on Saturn, which is hanging out with the star Spica in the constellation Virgo. On August 13, those three points of light will appear to line up, with Saturn above Mars above Spica. If it’s cloudy that night, August 21 will also provide a pretty view as the trio, stretching into a triangular configuration, is joined by the moon.

A new Mars rover named Curiosity is expected to land on the surface of the Red Planet around 10:30 pm PDT on August 5. If all goes as planned, the rover will begin exploring Gale Crater as it looks for water and past or present evidence of microbial life.

06/27/2012

As Earth orbits around the sun, new constellations and stars rise and become dominant during different seasons. In the summer, constellations from Sagittarius and Scorpius to Cygnus and Lyra are prominent due to their positioning in the sky. These constellations, extending from the southern horizon and tracing a trail overhead, also trace the path of the Milky Way.

From a suburban or rural location, wait until the sky gets dark on summer evenings and your eyes have adjusted, then seek out the cloudy-looking swath that begins in the south and arches overhead to the north. The Milky Way flows through the Summer Triangle (marked by the stars Vega, Deneb, and Altair) and thickens in the south near the Teapot asterism in Sagittarius, which is also the direction of the center of our galaxy.

The Milky Way Galaxy and our solar system are not aligned in parallel planes but intersect each other at an angle. Therefore, planets and the moon occasionally cross through the Milky Way as seen from our position. On July 29, the moon will appear to pass in front of the Milky Way, in the direction of the galaxy’s center.

With a pair of binoculars or a telescope, you can slowly sweep the environs of the Milky Way and stumble upon nebulae, star clusters, and globular clusters. The area just above the Teapot is an especially rich field for deep-sky objects.

05/30/2012

Did you invest in eclipse glasses to watch the May 20 annular/partial solar eclipse? If so, you are set for the Venus transit on June 5.

Venus passing in front of the sun as seen from Earth is a very rare occurrence and will not happen again until December 2117. The event begins when the spherical shape of the Goddess of Love edges in front of the sun, blocking out a bit of its rays. Through eclipse glasses, you will see a small black dot passing in front of the giant orange orb of the sun. If you don't have eclipse glasses, you can visit a local observatory, buy a solar filter for your telescope, or if it's cloudy you can watch one of the many web sites with a live feed of the event. (One to try is the Keck Observatory.)

In the United States, the transit occurs on June 5, while the Eastern Hemisphere will see the event on June 6. In the U.S., the event occurs near sunset, while in most of Europe, Africa, and western Asia, the event will be in progress at sunrise. Venus’s procession across the sun is slow, taking 6 hours and 40 minutes to traverse the northern half of the sun.

First contact (when Venus appears to touch the limb of the sun, also called ingress) occurs at 22:09:29 UT, which translates to 5:09 p.m. Central Time. Greatest contact will be at 1:29:28 UT, or 8:29 p.m. Central Time, which is about the time of sunset. For observers farther west, in San Francisco for example, the transit begins around 3:09 p.m. Pacific Time, with greatest contact right around 6:30 p.m., and the sun setting at 8:30 before the event completes at about 9:45 p.m.

04/27/2012

It's been many years since a solar eclipse of any kind swept across the mainland United States, but on May 20 an annular and partial solar eclipse will be visible for millions west of the Appalachian Mountains.

An annular eclipse is one in which the moon passes in front of the sun but cannot block it completely because it is near apogee, or its farthest point in its orbit from Earth. Therefore the moon appears a bit smaller in the sky and a ring of sunlight still seeps out from around the edges of the moon. Annular and partial eclipses are not safe to view without proper equipment, such as a solar filter, #14 welder's goggles, or a pinhole projection.

The path of the annular eclipse is a narrow one that begins in South China, sweeps across southern Japan before crossing the northern Pacific and landing in the United States near the Oregon/California border. The path continues southeasterly, passing over Lake Tahoe, a number of national parks including Zion, Bryce Canyon, and the Grand Canyon, and through Albuquerque before ending just east of Lubbock, Texas.

In Reno, the partial phase that leads up to the annular eclipse begins at 5:15 p.m., with the annular phase lasting from 6:28 to 6:32 p.m., and the partial phase ending at 7:37 p.m. In Albuquerque, the partial eclipse begins at 6:28, the annular lasts from 7:33 to 7:38, and the entire show wraps up by 8:36 p.m.

03/28/2012

Planet observing is the activity of the month. Jupiter and Venus are still bright in the west after sunset, while Mars is noticeable as the reddish point of light in the southeast and yellowish Saturn is rising in the east.

Concentrate on Jupiter to start with because it will be the first to leave the scene. The King of Planets looks great through a telescope, allowing you to spot the dark belts and light zones along with the four large Galilean satellites. Just above Jupiter is Venus, shining so brightly it often gets mistaken for an airplane. Through a telescope or binoculars you can spot the phase of Venus, which is shrinking throughout the month of April even while its overall size increases as it gets nearer to us. On the first few days of the month, watch as Venus nears and then appears to pass through the stars of the Pleiades cluster. Use binoculars for the best view.

Mars will be found not far from the bright star Regulus all month, while Saturn hovers near Spica in Virgo. Watch the moon as it hangs near Mars on April 3 and then shifts toward Saturn, reaching Spica and the Ringed Planet on April 6, the date of full moon.

April is host to one moderate meteor shower, the Lyrids, which occurs between April 16 and 25 with the peak of activity slated for the weekend of the 21st/22nd. Lyrid meteors appear to come from the constellation Lyra, which rises in the northeast midevening. Up to 20 meteors an hour is possible.

03/05/2012

Gavin Heffernan confessed to Sierra that he's addicted to time-lapse photography, and this dizzying video represents his latest fix. "It's like fishing - an escape from the madness," says the Los Angeles-based horror filmmaker. To get these shots of Joshua Tree National Park, he used a Canon EOS 7D with an EF-S18-135mm lens, and a Canon EOS 5D Mark II with an EF 24mm f1.4/L lens.

02/28/2012

If the night sky looks especially brilliant in early March, that's because it is. The six brightest objects in the night sky all appear at one time after sunset. The event will only last a couple days, though, as the brightness of two of the objects, Mercury and Mars, will begin to dim and lose their top night-sky rankings.

The six brightest objects in the sky are, in order, the moon, Venus, Jupiter, Mars, Mercury and the star Sirius. All six appear together after sunset on the first three days of March. They will still be visible after those days, but Mercury and Mars will be getting dimmer from their peak brightness. Starting in the west after the sun has set, look for Mercury close to the horizon. Dazzling Venus will be above Mercury, and Jupiter will be just above Venus. Look up to see the moon, and then south to find the star Sirius to the lower left of Orion. Lastly, the reddish dot of Mars can be easily discovered rising in the east.

The moon just made a couple of pretty pairings with Venus and Jupiter in late February, and it will meet up with the planets again as it goes through its cycle in March. On March 6 and 7, the moon will pass not far from Mars. Just a bit earlier, on March 5, Mars came its closest to Earth at 63 million miles distant. The full moon occurs on March 8, and at the end of the week, on March 10, the moon will be near the star Spica in Virgo and Saturn. March 25 will find the moon near Jupiter, and the next night it will be close to Venus.

01/27/2012

I was in high school when I got my first telescope. It was a Christmas gift, and I took it out of the box and assembled it in record time. Fortunately it was a clear night, so I hauled it outside on its rickety tripod mount and set it up in the backyard. Aiming it at the brightest "star" I saw, I fiddled with aligning the finderscope with the main tube and then inserted an eyepiece. After some focusing, BOOM, there it was: a bright sphere of light with faint points of light on either side of it. I rushed inside to dig through some magazines and books on astronomy that I kept in my bedroom. I felt pretty sure that I knew what I was looking at, I just didn’t know it was possible. After a little time spent sleuthing, sure enough, I read that not only was Jupiter up and bright on that December night, but with a little optical aid it was possible to see four of its moons. Even though Galileo had first seen Jupiter and its moons hundreds of years ago, my discovery of it on that cold Christmas night felt just as earth-shattering.

While amateur astronomers occasionally do make real discoveries, such as new comets and the like, when most of us observe we will only be discovering things that are new to us. It can still feel just as exciting to stare at the dark sky and let your eyes adjust and wait to see what appears. You may be able to trace out the constellation that winds between the Big and Little Dippers as you discover Draco for yourself, or spy a cozy little diamond grouping of stars in the summer sky and check a star chart to learn that this is the constellation Delphinus the Dolphin.

What can you discover on your next night out? The options are endless. All you need is a good star map (and there are many apps that work great for charting the sky and identifying objects) and some patience. This weekend after sunset as the stars begin to appear, examine the night sky. Do you know what the bright star is below Orion? Or the group of stars that looks like a V on its side? What about that orangish-looking "star" rising in the east? There are countless distant objects that are billions of years old waiting for you to discover them for the first time.

-- Kelly Kizer Whitt loves clean, clear, and dark skies. Kelly studied English and Astronomy at the University of Wisconsin-Madison and worked for Astronomy magazine. She writes the SkyGuide for AstronomyToday.com. You can follow her on Twitter at twitter.com/Astronomommy.

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